SYSTEMATIC AND BIOLOGICAL ACCOUNT 103 



that name in a work which is one of the standard references for the group. The legends to the 

 figures do not indicate the locality of the particular specimens, but presumably they came from the 

 Eastern Tropical Pacific. Much as I dislike having to criticize any part of Bigelow's delightful work 

 which I admire so much, there is one drawing, beautiful in its execution, which I mistrust, fig. 1 of 

 his plate 6. The only part of it which I query is the stiff base of the lamellar plates. The rest of the 

 drawing appears to represent 'G.' biloba (Sars), but in that species, as reference to my Text-fig. 50 of 

 the base of the anterior nectophore shows, the dorsal end of the lateral surfaces for articulation with 

 the posterior nectophore reaches well out below the ostium of the nectosac, in fact to a point not far 

 short of its centre. This means that the basal portion of the lamella or mouth-plate of the anterior 

 nectophore in 'G.' biloba is much more rigid than the thin distal part, which in preserved specimens 

 is usually bent back. Bigelow's fig. 1 of plate 6 does not show this feature, and is, I suspect, not correct. 

 It is not at all easy to draw this region even with a camera lucida, because it is only rarely that a specimen 

 is preserved in a satisfactory condition, and living material is not readily available. Then again this 

 fig. 1 of Bigelow does not show the little pit in the roof of the base of the anterior nectophore that 

 houses the tip of the stalk, a minor but a very characteristic feature of 'G.' biloba. It is of course 

 possible that Bigelow has accurately drawn a representative of a Pacific species that I have not seen, 

 but we are finding more and more that most siphonophores have very wide distributions and my 

 experience is based on hauls from a very extensive oceanic area. Besides, Bigelow's photograph 8 on 

 plate 5, though not strictly a side-view, shows all the characters of 'G.' biloba that I have mentioned. 

 The somatocyst and the basal pit are diagnostic, though the somatocyst does not show very clearly. 



Kawamura (19 15, fig. 10) tried, unsuccessfully, to fit together drawings 1 and 3 of Bigelow's plate 6, 

 but had to distort fig. 1, and left no space for the appendages. 



Bigelow & Sears (1937) attributed 514 anterior and 673 posterior nectophores from the Mediter- 

 ranean to this ' species ', australis. All of the posterior ones showed (in lateral view) ' the broad baso- 

 ventral sector' characteristic of both biloba and of turgida (see Bigelow, 191 ib, pi. 5, fig. 9, lateral 

 view — there are two figs. 9), and all had an undivided basal wing, which is a character of turgida. 

 Bigelow & Sears 's (1937) fig. 26 shows typical bases of turgida nectophores. 



The great breadth of this baso-ventral sector in 'G.' biloba and 'G.' turgida, which carries, at the 

 proximal end of each ventral wing, a long (dorso-ventrally) and rounded articulating surface, necessarily 

 implies that the base of the corresponding anterior nectophore is equally broad dorso-ventrally and 

 that the margins of the hydroecium are hollowed out to take these articulating surfaces which transmit 

 the thrust of the posterior nectophore. This condition is particularly well marked in the Mediterranean 

 species that I refer to below as 'G.' turgida. 



Bigelow & Sears (1937) also stated that these posterior nectophores from the Mediterranean have 

 undivided basal wings, but not, as I have already remarked, whether they have the duplex curve 

 mentioned on p. 35 of their 'Thor' report and figured by Bigelow (1911ft, pi. 5, fig. 9 bis). This is 

 important because in recent years Dr Gamulin has sent me from the Adriatic some well-preserved 

 specimens of anterior and posterior nectophores of a ' Galetta ' of which the posterior ones possess 

 a convexly rounded lamella, neither notched as in chuni nor with the duplex curve of Bigelow's figure 

 of ' australis', but like Gegenbaur's (1854) pi. XXIII, fig. 3. In fact I believe Gamulin's specimens are 

 the ' G.' turgida of Gegenbaur. The anterior nectophores have a much smaller somatocyst than Bigelow's 

 figures (1911ft, pi. 5, fig. 8; pi. 6, fig. 1) of australis, and resemble those in fig. 26 of Bigelow & Sears 

 (1937), which are in fact specimens of 'G.' turgida Gegenbaur. 



• At the end of September 1952, when the draft of this report had been completed, I was able to 

 re-examine, through the courtesy of Dr Kramp of the Copenhagen Museum, a number of the anterior 

 and posterior nectophores, separated into vials, from 'Thor' Stations 206 (1910) and 297 (191 1). 



